In the treatment of female patients, a physician on occasion finds it necessary to dilate and/or soften the cervix of the patient. Such dilation is frequently a prerequisite for placement and removal of intrauterine devices, induction of labor, radium placement, drainage of the uterine cavity, endometrial biopsy procedures, uterine curettage, and for a variety of other reasons. A variety of insertion elements used for dilation purposes are known to the art, and well-known among these is a cervical dilator employing a central longitudinally tapered rod-like insertion element made from the root stalk of a seaweed known as laminaria japonica, such insertion elements having been used for over one hundred years for insertion into the cervix to expand the cervical canal. The prior art has long recognized the unique property of this material, namely that when inserted in the dry state into the cervical canal a rod of given diameter will, upon absorption of fluids normally present in the cervical canal expand principally in the radial direction by a factor of 200 to 300 percent. This action slowly and automatically expands the canal over a period of several hours. These elements are normally both inserted and removed by a physician.
A rigid disc-like collar member is generally placed around the rod-like dilator element to act as a stop shoulder to limit the degree of extension of the dilator element into the cervical canal. This prevents premature migration of an inserted dilator element undesirably high in the cervical canal before the requisite anchoring expansion takes place. The stop collar member has a central aperture which receives the dilator element which projects both forwardly and rearwardly therefrom. The collar member has a diameter much larger than the diameter of the entrance of the cervical canal. The collar member initially is held upon the dilator element only by friction between the dilator element press-fitted into the collar member and the defining wall of the collar aperture.
Usually a thread loop is affixed to the rear of the dilator element through a small passage drilled therethrough, the thread serving as a tell-tale to assist the physician in locating the end of the dilator element for withdrawal thereof. The structural strength of the stalk is inadequate, particularly in the wet and expanded form, to support sufficient force to allow the cord to be used reliably for extraction purposes; hence the physician normally uses the cord only as a "tell-tale" to aid in locating the dilator element so that it can be withdrawn by application of forceps. Sometimes if the physician uses the cord to pull the dilator element from the cervical canal, the cord tears through the element before it is completely removed from the canal.
It would be a useful feature to be able to reliably secure such a cord to the dilator element in such a way that the element may be withdrawn by a pulling force on the cord without tearing it loose therefrom. While it would seem possible to securely anchor the cord by using suitable adhesives for this purpose, to the applicant's knowledge this has not heretofore been done, probably because chemical adhesives can possibly be torn or act as an irritant within the cervical canal.